Somewhat rough running at low RPM's with EAT chip

[repenttokyo]

I installed an EAT chip in my 91 M50 5 speed last friday. I don't know if I am imagining it, but at low rpm's in 2nd and 3rd gear (2k and below), I am feeling a strange vibration, and almost a hesitation. Never had these issues before the chip install. Is this normal? Is the advanced timing revealing problems with my motor? Could it be spark plugs, or carbon build up?

[repenttokyo]

I ran the car quite hard breaking in the new chip, could this have something to do with it?

[spyrot1]

What kind of gasoline are you using?

[Fetch]

Swap back to stock chip and check for symptoms.

[repenttokyo]

I have been using 91 octane and now 94.

Considering that these symptoms started the day I installed the new chip, it leads me to believe that the new chip is the cause. I haven't made any other changes to the car. I disconnected the battery tonight and I will reconnect tomorrow morning and perform a less aggressive break in to see if that alleviates the problem.